Front Release Buckle

ABSTRACT

A front release buckle of the invention includes a plug and a socket. The plug includes: a base; a leg that projects from the base; and an engaging portion formed to the leg. The socket includes: a body having an insertion opening; a housing space that is defined inside the body and capable of housing the leg inserted through the insertion opening; an engaged portion that is formed on the body and engageable with the engaging portion; and a manipulation portion that disengages an engagement between the engaging portion and the engaged portion. The plug and the socket are formed to be flat. The leg is flat and flexible in a thickness direction. The engaging portion and the engaged portion are engaged with each other in the thickness direction. The engaging portion projects in a width direction of the leg and is formed within the thickness of the leg.

TECHNICAL FIELD

The present invention relates to a front release buckle in which a top part is manipulated for releasing an engagement.

BACKGROUND ART

There has been typically used a buckle that detachably engages a plug with a socket in order to couple a string member such as a belt in various applications such as clothes, bags, shoes and packages.

Such a buckle is required to be easily handled for coupling and releasing and not to cause an accidental release when the buckle is not intended to be released. As a product responding to such needs, a front release buckle in which a top part is manipulated for releasing an engagement has been used.

There has been known a front release buckle in which a plug and a socket are engaged to each other to be locked.

For instance, Patent Literature 1 discloses a flat buckle in which a locking lug (i.e., a convex engaging portion of a plug) projects in a thickness direction of the buckle.

Patent Literature 2 discloses a flat buckle in which a first convex portion to be engaged with a socket is provided at an end of a plug and projects in a thickness direction of the buckle.

CITATION LIST Patent Literature(s)

Patent Literature 1 Japanese Patent No. 3248104

Patent Literature 2 JP-A-2006-204619

SUMMARY OF THE INVENTION Problems to be Solved by the Invention

In the buckle disclosed in Patent Literatures 1 and 2, since the locking lug projects in the thickness direction of the buckle, the thickness of the buckle becomes large. Accordingly, for instance, when such a buckle is used in a rucksack and the like, due to a large thickness of the buckle, a position where the buckle is attached in the rucksack may be limited, or a whole design of the rucksack may be adversely affected.

Accordingly, an object of the invention is to provide a front release buckle with a reduced thickness.

Means for Solving the Problems

A front release buckle according to an aspect of the invention includes a plug; and a socket into which the plug is inserted for engagement, in which the plug includes: a base; a leg that projects from the base; and an engaging portion that is formed to the leg, the socket includes: a body having an insertion opening; a housing space that is defined inside the body and capable of housing the leg inserted through the insertion opening; an engaged portion that is formed on the body and engageable with the engaging portion; and a manipulation portion that disengages an engagement between the engaging portion and the engaged portion, the plug and the socket are formed to be flat, the leg is flat and flexible in a thickness direction, the engaging portion and the engaged portion are engaged with each other in the thickness direction, and the engaging portion projects in a width direction of the leg and is formed within the thickness of the leg.

In the above aspect of the invention, since the engaging portion of the plug projects in the width direction, not in the thickness direction, the thickness of the socket housing the plug and the engaging portion is reducible. Accordingly, the thickness of the buckle does not become large but is reducible. For instance, when a front release buckle having such a small thickness is used in a rucksack or the like, a position where the buckle is attached in the rucksack is not limited because of the small thickness of the buckle. Moreover, because of the small thickness of the buckle, the buckle becomes less noticeable and is not caught to cause no adverse effects on a whole design of the rucksack or the like.

In the above aspect of the invention, it is desirable that, in an engagement between the plug and the socket, the manipulation portion and the engaging portion are positioned in a manner capable of contacting with each other, the manipulation portion is positioned in the thickness direction of the leg to face the leg and has flexibility in the thickness direction, and the manipulation portion includes a projection projecting inward of the socket.

With this arrangement, the projection is pressed onto the leg by flexing the manipulation portion toward the engaging portion. At this time, since the engagement between the engaging portion and the engaged portion is released, the leg can be pushed out toward the insertion opening of the socket.

In the above aspect of the invention, it is desirable that the engaging portion includes inclined portions respectively having inclined surfaces near the manipulation portion, and the manipulation portion is flexed toward the engaging portion to cause the projection to press the inclined surfaces.

With this arrangement, the projection is pressed onto the inclined surface by flexing the manipulation portion toward the engaging portion. At this time, since the projection is flexed toward the engaging portion while sliding on the inclined surface, the engagement between the engaging portion and the engaged portion is released while the engaging portion is pushed out toward the insertion opening of the socket. Thus, when the manipulation portion is pressed, the plug is separated and pushed out from the socket. Accordingly, the plug can be reliably separated from the socket by only pressing the manipulation portion.

In the above aspect of the invention, it is desirable that an angle of each of the inclined surfaces is 15 degrees.

With this arrangement, since the angle of each of the inclined surfaces is 15 degrees, the projection can smoothly slide on the inclined surfaces. Accordingly, when the manipulation portion is pressed, the plug is separated and smoothly pushed out from the socket. Consequently, the plug can be more reliably separated from the socket by only pressing the manipulation portion.

In the above aspect of the invention, it is desirable that the front release buckle further includes a pair of holders that position and hold the plug projecting from the base and the socket.

With this arrangement, since the pair of the holders to position and hold the plug and the socket are provided, the engagement between the engaging portion and the engaged portion can be reliably made. Moreover, for instance, when a twisting stress is applied on the plug and the socket, the plug and the socket are not displaced, so that the engagement between the engaging portion and the engaged portion can be reliably maintained without any possibility of being released, whereby a function as a buckle is achievable.

In the above aspect of the invention, it is desirable that the leg diagonally projects in a manner to approach the manipulation portion as the leg extends in an insertion direction.

With this arrangement, since the leg projecting from the base is closer to the manipulation portion than the holders are, when the manipulation portion is pressed, the engaging portion can be pressed with a slight flexure of the manipulation portion. Accordingly, even when the thickness of the front release buckle is reduced, the plug can be separated and pushed out from the socket by pressing the manipulation portion. Consequently, the thickness of the front release buckle can be further reduced.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a plan view showing an overall structure according to an exemplary embodiment of the invention.

FIG. 2 is a side elevation showing the overall structure according to the above exemplary embodiment.

FIG. 3 is a front view showing the overall structure according to the above exemplary embodiment.

FIG. 4 is a plan view of a plug according to the above exemplary embodiment.

FIG. 5 is a side elevation of the plug according to the above exemplary embodiment.

FIG. 6 is a plan view of a socket according to the above exemplary embodiment.

FIG. 7 is a side elevation of the socket according to the above exemplary embodiment.

FIG. 8 is a front view of the socket according to the above exemplary embodiment.

FIG. 9 is a cross-sectional view of a manipulation portion of the socket according to the above exemplary embodiment.

FIG. 10 is a cross-sectional view showing an engagement between the plug and the socket according to the above exemplary embodiment.

FIG. 11 is a cross-sectional view showing a state where the plug and the socket are being engaged according to the above exemplary embodiment.

FIG. 12 shows a state in which an engaging portion is pushed out by flexure of the manipulation portion in the above exemplary embodiment.

FIG. 13 is a plan view showing a plug according to another exemplary embodiment of the invention.

FIG. 14 is a plan view showing a plug according to still another exemplary embodiment of the invention.

FIG. 15 is a plan view showing a plug according to a further exemplary embodiment of the invention.

FIG. 16 is a plan view showing a plug according to a still further exemplary embodiment of the invention.

DESCRIPTION OF EMBODIMENT(S)

An exemplary embodiment of the invention will be described below with reference to the attached drawings.

FIGS. 1 to 12 show an exemplary embodiment of the invention.

An overall structure of a front release buckle will be described below with reference to FIGS. 1 to 3.

FIG. 1 is a plan view showing the overall structure according to the exemplary embodiment of the invention. FIG. 2 is a side elevation showing the overall structure according to the above exemplary embodiment. FIG. 3 is a front view showing the overall structure according to the above exemplary embodiment.

As shown in FIGS. 1 to 3, a front release buckle 1 according to this exemplary embodiment includes a plug 10 and a socket 20 into which the plug 10 is inserted for engagement.

As shown in the figures, the front release buckle 1 according to this exemplary embodiment is used to couple and separate ends of a string member such as a belt. The front release buckle 1 includes the plug 10 integrally formed of a synthetic resin and the socket 20 also integrally formed of a synthetic resin.

The plug 10 and the socket 20 may be formed of other materials such as metal instead of a synthetic resin according to other molding methods (e.g., rapid manufacturing and casting) instead of an injection molding.

A structure of the plug will be described with reference to FIGS. 4 and 5.

FIG. 4 is a plan view of the plug according to the above exemplary embodiment. FIG. 5 is a side elevation of the plug according to the above exemplary embodiment.

In FIGS. 4 and 5, an entirety of the plug 10 is integrally formed of a synthetic resin by injection molding. The plug 10 includes a base 11 having a pair of legs 12, an engaging portion 14 formed in each of the legs 12, and a belt attachment 19 into which a belt or the like is inserted.

The legs 12 extend in parallel to each other in a length direction of the base 11 (an insertion direction of the plug 10 to the socket 20, i.e., in a vertical direction in FIG. 1) from both sides of the base 11 in a width direction (a direction orthogonal to the insertion direction of the plug 10 to the socket 20 and a thickness direction of the socket 20, i.e., a horizontal direction in FIG. 1). A portion from the middle to the tip end of each of the legs 12 is elastically deformable in a thickness direction (i.e., a direction orthogonal to the width direction and the insertion direction described above).

The pair of legs 12 are inclined in such a manner to approach a manipulation portion 27A as the legs 12 extend in the insertion direction, so that an entirety of the legs 12 can receive a force for elastic deformation in the thickness direction.

The engaging portion 14 is formed as a projection extending from the tip end of each of the legs 12 in the width direction. The tip end of each of the legs 12 is T-shaped in a plan view. The engaging portion 14 formed at the tip end of each of the legs 12 is formed to have a thickness (i.e., height) that does not exceed a height of each of the legs 12.

The engaging portion 14 includes an inclined portion 14B that is formed at the tip end of each of the legs 12, and a connecting inclined portion 14D that connects the inclined portions 14B in the width direction. With this connecting inclined portion 14D, the pair of legs 12 are restricted from being deformed in the width direction by an external force. Further, when the pair of legs 12 are elastically deformed in the thickness direction, this connecting inclined portion 14D allows the pair of legs 12 to be deformed by the same volume.

The inclined portion 14B includes an inclined surface 14A that is gradually inclined so that the thickness of the engaging portion 14 becomes smaller toward the tip end of each of the legs 12 in the insertion direction. The connecting inclined portion 14D includes a connecting inclined surface 14C.

As shown in FIG. 5, a pair of holders 16 are provided at outer sides of the pair of legs 12. The pair of holders 16 are rod-like members that are disposed on the base 11 apart from each other in the width direction of the base 11 and extend in the insertion direction. A tip end of each of the pair of holders 16 is spaced apart from the engaging portion 14. A thickness of each of the holders 16 is formed to be smaller than the thickness of the base 11 and larger than thickness of each of the legs 12.

Each of the holders 16 includes a projecting holder 16A that is provided along an outer side of the each of the holders 16 in the width direction.

The engaging portion 14 and the holders 16 are guided by undulations (described later) formed on an inner side of the socket 20 so that the plug 10 is guided to an appropriate position during an insertion operation.

As shown in FIG. 4, the belt attachment 19 is formed in a middle area of the base 11. The belt attachment 19 includes: a belt attachment hole 19A that is provided in the middle of the inside of the belt attachment 19 and into which an end of the belt is inserted; a first bar 19B that extends in the width direction of the plug 10 in a manner to bridge over the plug 10 between the ends of the plug 10 (i.e., the ends of the base 11); and a second bar 19C that is formed in the middle of the belt attachment hole 19A in a manner to bridge over the belt attachment hole 19A. The second bar 19C divides the belt attachment hole 19A into an insertion-direction front hole 19D and an insertion-direction rear hole 19E.

With this arrangement, when a belt (not shown) is inserted into the belt attachment hole 19A and wound around the second bar 19C to be contacted with the first bar 19B, the belt can be engaged and fixed to the plug while a length of the belt can be adjusted.

A structure of the socket will be described with reference to FIGS. 1 and 6 to 8.

FIG. 6 is a plan view of the socket according to the above exemplary embodiment. FIG. 7 is a side elevation of the socket according to the above exemplary embodiment. FIG. 8 is a front view showing the socket according to the above exemplary embodiment.

In FIGS. 1 and 6 to 8, an entirety of the socket 20 is integrally formed of a synthetic resin by injection molding. The socket 20 includes: a hollow cylindrical body 21 having an insertion opening 22; a housing space 23 being formed in the body 21 and capable of housing the legs 12 of the plug 10 to be inserted through the insertion opening 22; an engaged portion 24 being formed in the body 21 and engageable with the engaging portion 14; a manipulation opening 27 being formed in the center in a plan view of the body 21; an opening 28 being formed at a position corresponding to the engaging portion when the socket is engaged with the plug; and a belt attachment 29 into which a belt (not shown) is inserted.

The engaged portion 24 is a wedge-shaped member having an inclined surface facing the insertion opening 22 and being formed inside the housing space 23 at two positions spaced apart from each other in the width direction. The engaged portions 24 are formed on an inner side of a top surface of the body 21 and project into the housing space 23.

A thickness of the engaged portion 24 is formed to be smaller than a thickness of the housing space 23 and corresponds to the thickness of the engaging portion 14 formed to each of the pair of legs 12.

A guide surface 25 is formed inside the housing space 23 to guide the engaging portion 14 to the engaged portion 24 for engagement.

On the guide surface 25, a plurality of pairs of grooves 26 are formed in the insertion direction from an end of the insertion opening 22. When the legs 12 and holders 16 are inserted from the insertion opening 22, convex portions (not shown) formed on a bottom surface of each of the legs 12 mates with the grooves 26, where the grooves 26 serve as a guide to lead the engaging portions 14 formed at the tip ends of the legs 12 to the engaged portions 24.

A structure of the manipulation portion of the socket will be described with reference to FIG. 9.

FIG. 9 is a cross-sectional view of the manipulation portion of the socket according to the above exemplary embodiment.

As shown in FIG. 9, in order to release the engagement of the engaging portion 14 and the engaged portion 24, the manipulation opening 27 is formed in the center of the body 21 in a plan view. The manipulation opening 27 communicates with the housing space 23 inside the body 21.

The manipulation opening 27 is formed at a position where the connecting inclined portion 14D that connects the legs 12 inserted from the insertion opening 22 is exposed.

The manipulation portion 27A is a flexible member that is elastically deformable in the thickness of the socket by being pressed, the manipulation portion 27A being provided to the manipulation opening 27. The manipulation portion 27A is positioned to face the legs 12 and is configured to be contacted with the connecting inclined portion 14D by being elastically deformed. The manipulation portion 27A includes a projection 27B that is positioned to be contacted with the connecting inclined portion 14D and projects inward in the thickness direction of the socket and a thick portion 27C that corresponds to the projection 27B and projects outward in the thickness direction.

With reference to FIGS. 9 to 12, a state where the plug and the socket are being engaged, a state where the plug and the socket have been engaged and a state where the engagement between the plug and socket is released will be described.

FIG. 10 is a cross-sectional view showing the engagement between the plug and the socket according to the above exemplary embodiment. FIG. 11 is a cross-sectional view showing a state where the plug and the socket are being engaged according to the above exemplary embodiment. FIG. 12 is an enlarged cross-sectional view showing a state in which the engaging portion is pushed out by flexure of the manipulation portion in the above exemplary embodiment.

As shown in FIGS. 9 and 11, when a pair of engaging portions 14, which are located at the tip ends of the legs 12 inserted through the insertion opening 22, are guided by the guide surfaces 25 to reach the engaged portions 24, the pair of legs 12 are elastically deformed to be respectively engaged with the engaged portions 24.

On the other hand, as shown in FIGS. 10 and 12, by pressing the connecting inclined portion 14D, the projection 27B elastically deforms the legs 12 in the thickness direction while sliding on the connecting inclined surface 14C. With this operation, the engagement between the engaging portions 14 and the engaged portions 24 is released and the plug 10 is pushed out toward the insertion opening 22.

In the above exemplary embodiment, the following advantages are attainable.

In the front release buckle 1 according to the exemplary embodiment, since the engaging portion 14 of the plug 10 projects not in the thickness direction but in the width direction, the thickness of the buckle is not increased but can be reduced. Accordingly, for instance, when the front release buckle 1 having a small thickness is used in a rucksack or the like, a position where the buckle is attached in the rucksack is not limited because of the small thickness of the buckle. Moreover, because of the small thickness of the buckle 1, the buckle is unnoticeable to cause no adverse effects on a whole design of the rucksack or the like.

In the front release buckle 1 of the exemplary embodiment, the manipulation portion 27A is flexed toward the engaging portion 14, whereby the projection 27B presses the connecting inclined surface 14C. At this time, since the projection 27B is flexed toward the engaging portion 14 while sliding on the connecting inclined surface 14C, the engagement between the engaging portion 14 and the engaged portion 24 is released while the engaging portion 14 is pushed out toward the insertion opening 22 of the socket 20. Accordingly, when the manipulation portion 27A is pressed, the plug 10 is separated and pushed out from the socket 20. Thus, the plug 10 can be reliably separated from the socket 20 by only pressing the manipulation portion 27A.

In the front release buckle 1 of the exemplary embodiment, since an angle of the connecting inclined surface 14C is 15 degrees, the projection 27B can slide smoothly on the connecting inclined surface 14C. Accordingly, when the manipulation portion 27A is pressed, the plug 10 is separated and smoothly pushed out from the socket 20. Thus, the plug 10 can be more reliably separated from the socket 20 by only pressing the manipulation portion 27A.

In the front release buckle 1 of the exemplary embodiment, since the pair of the holders 16 to position and hold the plug 10 and the socket 20 are provided, the engagement between the engaging portion 14 and the engaged portion 24 can be reliably made. Moreover, for instance, when a twisting stress is applied on the plug 10 and the socket 20, the plug 10 and the socket 20 are not displaced, so that the engagement between the engaging portion 14 and the engaged portion 24 can be reliably maintained without any possibility of being released, whereby a function as a buckle is achievable.

In the front release buckle 1 of the exemplary embodiment, since the legs 12 projecting from the base 11 are closer to the manipulation portion 27A than the holders 16 are, a slight flexure of the manipulation portion 27A when being pressed is required for pressing the engaging portion 14. Accordingly, even when the thickness of the front release buckle 1 is reduced, the plug 10 can be separated and pushed out from the socket 20 by pressing the manipulation portion 27A. Consequently, the thickness of the front release buckle 1 can be further reduced.

Modifications

It should be noted that the invention is not limited to the above arrangements of the exemplary embodiments but encompasses the following modifications.

The structure of the pair of legs 12 is not limited to the structure that the pair of legs 12 are connected with each other through the connecting inclined portion 14D as described in the above exemplary embodiment. However, as shown in FIG. 13, the pair of legs 12 may be configured to be independent without being connected with each other. In such a case, it is preferable to increase a width of the projection 27B so as to press the inclined surface 14A.

The engaging portion 14 may not be the projection extending outward in the width direction of the legs 12 from the tip end of each of the legs 12, but, as shown in FIG. 14, may be a projection extending inward in the width direction, in which the inclined portion 14B may be provided on a side opposite to the tip end of each of the legs 12 in the insertion direction.

Further, the engaging portion 14 is not necessarily formed in an L-shape. As shown in FIG. 15, the engaging portion 14 may be provided by a single body.

Moreover, the legs 12 are not necessarily formed in a pair. As shown in FIG. 16, the legs 12 may be provided by three legs.

INDUSTRIAL APPLICABILITY

The invention is usable as a front release buckle that connects a belt and is provided with a pair of lock arms.

Explanation of Codes

-   1: front release buckle -   10: plug -   11: base -   12: leg(s) -   14: engaging portion(s) -   14A: inclined surface(s) -   14B: inclined portion(s) -   16: holder(s) -   20: socket -   21: body -   22: insertion opening -   23: housing space -   24: engaged portion(s) -   27A: manipulation portion -   27B: projection 

1. A front release buckle comprising: a plug; and a socket into which the plug is inserted for engagement, wherein the plug comprises: a base; a leg that projects from the base; and an engaging portion that is formed to the leg, the socket comprises: a body having an insertion opening; a housing space that is defined inside the body and capable of housing the leg inserted through the insertion opening; an engaged portion that is formed on the body and engageable with the engaging portion; and a manipulation portion that disengages an engagement between the engaging portion and the engaged portion, the plug and the socket are formed to be flat, the leg is flat and flexible in a thickness direction, the engaging portion and the engaged portion are engaged with each other in the thickness direction, and the engaging portion projects in a width direction of the leg and is formed within the thickness of the leg.
 2. The front release buckle according to claim 1, wherein in an engagement between the plug and the socket, the manipulation portion and the engaging portion are positioned in a manner capable of contacting with each other, the manipulation portion is positioned in the thickness direction of the leg to face the leg and has flexibility in the thickness direction, and the manipulation portion comprises a projection projecting inward of the socket.
 3. The front release buckle according to claim 1, wherein the engaging portion comprises inclined portions respectively having inclined surfaces near the manipulation portion, and the manipulation portion is flexed toward the engaging portion to cause the projection to press the inclined surfaces.
 4. The front release buckle according to claim 3, wherein an angle of each of the inclined surfaces is 15 degrees.
 5. The front release buckle according to claim 1, further comprising: a pair of holders that position and hold the plug projecting from the base and the socket.
 6. The front release buckle according to claim 5, wherein the leg diagonally projects in a manner to approach the manipulation portion as the leg extends in an insertion direction. 